Of course I don't know if U106 in Kazakhstan came from Germans most likely from the Baskhirs who have R1b, since there was 30,000 of them enslaved to Kazakhstan. Point was there over 100,000-200,000+ Europeans already existed in Central Asia and Kazakhstan long before Soviet control of central Asia.
A portion of Kazakhs western eurasian mtDNA seem to be related with European mtDNA but I wouldn't know if it's ancient or recent.